Reduction of respiratory muscle strength in subjects with rheumatoid arthritis

Objective: To evaluate the respiratory muscle strength in patients with rheumatoid arthritis (RA) compared to healthy subjects and to correlate it with the level of disease activity (DAS- 28) and body mass index (BMI). Method: A cross-sectional study evaluated 18 women (57.94 ± 10.36 years); eight had RA (RA group) and ten were healthy subjects (control group), matched by age. All patients underwent the following evaluations: registration form (identification and clinical data), physical examination (weight, height, and BMI), DAS-28, dosage of C-reactive protein (CRP), and measurement of MIP and MEP with a manometer. Results: There were significant differences between the RA and control groups in relation to the MIP (-46.25 ± 17.67 vs. cmH2O -81.00 ± 19.69 cm H2O) and MEP (58.75 cmH2O ± 17.26 vs. 78.00 ± 6.32 cmH2O). Also there was difference between RA group and predicted age values in relation to the MIP (-46.25 ± 17.67 vs. -81.06 ± 4.11 cmH2O) and MEP (58.75 cmH2O ± 17.26 vs. 78.92 ± 5.33 cmH2O). Moreover, a significant correlation was observed between MEP and BMI. There was no significant correlation between MIP - CRP, DAS- 28 and BMI, and between MEP - DAS and CRP. Conclusion: This data reinforces the systemic nature of RA and points out the need for a comprehensive assessment of the patient, not just focusing on the articular component, but also checking the strength of the respiratory muscles of these individuals to determine more specific therapeutic strategies of treatment.